1. Field of the Invention
The present invention relates to a capacitance unit and a stacked solid electrolytic capacitor. In particular, the present invention relates to a capacitance unit and a stacked solid electrolytic capacitor having uniform thickness.
2. Description of Related Art
Capacitors are widely used in modern electronic products for storing electrical charge, filtering, bypassing or tune-oscillating. Because of the different capacitor properties, capacitors in different types are chosen in different applications. Solid electrolytic capacitors have properties of high capacity, a small size, high-frequency characteristics and low manufacturing cost; therefore, the solid electrolytic capacitors are more and more used in various applications, such as electric devices and electronic products.
Please refer to FIGS. 1A and 1B; the traditional capacitors are shown. Due to the structure and the manufacturing processes in the traditional method, it is needed to change the size and the shape of the traditional capacitor. For example, the difference between the front-end thickness S1 and the rear-end thickness S2 is large; therefore, the stacked capacitor unit similarly has an issue of un-uniform thickness between the front-end thickness W1 and the rear-end thickness W2. The thicker end of the stacked capacitor unit, i.e., the rear end, results in the thin wall thickness of the packaging material. Further, the thin wall thickness of the packaging material causes the low mechanical strength of the packaging material so that the inner material may be exposed easily, or the airtightness of the packaging material may be decreased. In other words, the moisture may affect the capacitor performance so that the electrical properties of the capacitor are un-stable and the current leakage may occur.
The above-mentioned issues affect the capacitor performance and the safety of the electrical circuit. What is needed is providing solid electrolytic capacitors and stacked solid electrolytic capacitors that have small sizes, uniform thicknesses and high packaging strength to overcome the foregoing disadvantages.